This script uses the -Z option to
dtrace, allowing it to be run when there is no
PHP process executing. If this option were omitted the script
would immediately terminate because it knows none of the probes to
be monitored are in existence.

The script traces all core PHP static probe points throughout the
duration of a running PHP script. Run the D script:

# ./all_probes.d

Run a PHP script or application. The monitoring D script will
output each probe's arguments as it fires.

When monitoring is complete, the D script can be terminated with a
^C.

On multi-CPU machines the probe ordering might not appear to be
sequential. This depends on which CPU was processing the probes,
and how threads migrate across CPUs. Displaying probe time stamps
will help reduce confusion, for example: